This invention relates to a method of treatment for muscular dystrophy and, more particularly, to a method of treatment for muscular dystrophy such as Duchenne muscular dystrophy, Becker muscular dystrophy and the like.
The Duchenne muscular dystrophy is a sex-linked recessive disease occuring in childhood, in which muscle weakness and muscular wasting in the proximal parts of extremities and trunk are progressed, resulting in a death at about twenty. The Becker muscular dystrophy is also a sex-linked recessive disease showing the same symptoms, although its onset age is older and tile progression is slower, compared with the Duchenne type.
Other muscular dystrophies include limb-girdle muscular dystrophy, facioscapulohumeral (FSH) muscular dystrophy, congenital muscular dystrophy, and the like.
Studies on these muscular dystrophies were widely made through many years in developed countries as leaders, with respect to the etiological cause, mechanism of incidence, medical treatment and the like, but, an effective medical treatment so far has not been established yet. Thus the earliest possible development of an effective remedy has long been awaited. Up to the present time, number of medicines were examined for their possibilities as the remedy, but prednisolone, a known 11-betahydroxy corticosteroid, and dantrolene are merely reported to be slightly effective.
Glyeyrrhizin has been used as a remedy for liver diseases and an anti-allergic medicine for many years, and its effectiveness is recognized. Although it causes hypokalemia as a side effect, this is relatively easy to control by the combined use with spironolactone. Further, glycyrrhizin is known to enhance the effects of adrenal cortical hormones by the suppression of metabolism of them, and it is also expected to reduce the side effect of prednisolone by the combined use with prednisolone.
However, glycyrrhizin has not been examined as a remedy for muscular dystrophy, and there has been no report on its effectiveness yet.
With respect to the prednisolone and dantrolene as the remedy for muscular dystrophy, it is the present state that troublesome adverse effects by their long-term use such as the production of a difficult side effect such as Cushing syndrome at a high ratio in case of the prednisolone and the induction of a liver damage in case of the dantrolene can not be avoided. The single use of these medicines can not provide a sufficient effect, and a new drug is desired which is well tolerated to the patients with muscular dystrophies for a long period, and can be used as an adjunctive therofy to prednisolone or dantrolene.